Very interesting.
Looks like a day camp project.
In the fifties day camp counselers taught us how to make potato stamps. Heaven forbid! Five year olds armed with paring knives in the woods!
Then again. it was just after the OSS was reformed as the CIA and the day trips were in the DC area. They never told us we were being scouted and trained for document forgery
Looking back that blue USDA ink looked quite like border crossing stamps in visas. hmmm....
That sort of thing could never happen today as we had to bring our own potatoes along with our bag lunches.
Just imagine the comms overload with parents asking what kind of potatoes?
Russet? Yukon Gold, new potatoes, Idahos? We only eat sweet potatoes, would that be all right? Can we download a list? There won’t be peanuts along will there?
Knives!!! ...end call.